Mineral lubricating oil containing bisphenol, detergent and phosphite additive



United States Patent MINERAL LUBRICATING OIL CONTAINING BIS- PHENOL,DETERGENT AND PHOSPHITE ADDI- TIVE Duk Hi Lee, Berkeley, Calif.,assignor to Shell Oil Company, New York, N.Y., a corporation of DelawareNo Drawing. Filed Apr. 30, 1964,'Ser. No. 363,976

4 Claims. (Cl. 252-461) This invention relates to new and improvedmineral lubricating oil compositions containing ashless polymericdetergents.

g It is known that phenolic compounds and particularly alkylatedbisphenols as described in US. Patents 2,807,653 and 2,944,086 are goodoxidation inhibitors for lubricating oils, greases, rubbers, waxes, andthe like. The art also teaches that these bisphenols for-m synergisticantioxidant mixtures with certain classes of diaryl acid phosphates ororgano-Z-thiaphosphono compounds such as dodecyl-Z-thiamethylphosphonicacid and esters thereof.

Although it has been observed that benefits are imparted to lubricatingoils by addition of bisphenols or mixtures of these bisphenols andpentavalent phosphorouscontaining compounds as mentioned with respect tooxidation stability and wear inhibition, it has been found that theaddition of such additive mixtures to mineral lubricating oilscontaining certain types of ashless polymeric detergents results in .adecrease of detergent life, resulting in dirty engines in a relativelyshort period of engine operating time, particularly when the engine isoperating at elevated temperatures and pressures or under stop-andgodriving conditions.

It has now been discovered that the detergent life of minerallubricating oils containing ashless polymeric detergents as will behereinbelow described can be greatly increased by addition of a minoramount of an additive mixture comprising '(A)' an alkylated bisphenolhaving the general formula L. (X), (I)

where Y- is a methylene radical or sulfur, X is a halogen, preferably amiddle halogen (C1 or Br), R is a tertiary alkyl radical of from 48carbon atoms, m is an integer of 1-3, preferably 2, and n is an integerof zero or 1 and (B) an organic phosphite having the formula where Z isoxygen and/r sulfur, R is an aryl or alkaryl radical having 6-18,preferably 6-12 carbon atoms and the 'sum of x and y is 3 and such thatx is at least 2 and y can be zero or 1 and preferably such that x is 3and y is zero.

The alkylated bisphenols represented by Formula I include alkylatedbisphenol sulfides such as bis(2,5-dipentyl- 4 hydroxyphenyl) sulfide,bis(2,5 dihexyl 3 hydroxypwhenyDsulfide, bis(2 methyl 5 tertiary butyl-4-hydroxyphenyl)sulfide, bis(Z-methyl-S-tertiarybutyl-6-hydroxyphenyl)sulfide and particularly bis(3-tertiarybutyl-S-methyl-Z-hydroxyphenyl) sulfide.

The alkylated bisphenols having a methylene bridge, includebis(2,3-di-tertiarybutyl-4-hydroxyphenyl)methane,bis(2,S-di-tertiarybutyl-4-hydroxyphenyl)methane, bis(2,-G-di-tertiarybutyl-4-hydroxyphenyl)-methane, bis(3,5-ditertiaryoctyl 4hydroxyphenyl)methane, bis(3 tertiarybutyl 5 tertiaryoctyl 4hydroxyephenynmethane,

3,296,134 Patented Jan. 3, 1967 and especially bis(3,5 di tertiarybutyl4 hydroxyphenyl)methane. The halogen containing bisphenols areillustrated by bis(2 chloro 5 tertiarybutyl 4 hydroxyphenyl)methane,bis(2 bromo 5 tertiarybutyl 4 hydroxyphenyDmethane, bis(2 chloro 5tertiarybutyl- 4- hydroxyphenyDsulfide and mixtures thereof.

The organic phosphites of Formula II and preferably phosphites havingthe formula P(OR") (Ha) (Ia) Tritolyl phosphite (0.15%) and-bis(3,5-di-tertiary- =butyl-4-hydroxyphenyl)metlhane (0.15%)

(Ha) Tritolyl thiophosphite (1.0%) andbis(3,5-di-tertiarybutyl-4-hydroxyphenyl)methane (0.15%

(Illa) Triphenyl phosp-hite (0.5 andbis(3,5-di-tertiarybutyl-4-hydroxyphenyl)methane (0.1

The oil-soluble polymeric detergents which are present 7 in minerallubricating oils of the present invention and whose detergent life isimproved and increased include oxygenor oxygen and nitrogencontainingpolymeric detergents. i

The nitrogen-containing polymeric detergents are copolymers of monomershaving polymerized linkages and containing nitrogen-containing groupswhich may be amino or amido groups. They may be derived frompolymerizable monomers containing primary, secondary or tertiary (thelatter two are preferred) amino nitrogen, including heterocyclic aminoor amido nitrogen-containing substances, having an ethylenicallyunsaturated polymerizable group. These detergent polymers may beobtained by polymerizing vinyl substituted heterocyclicnitrogen-containing substances such as vinyl pyridine, vinyl picolineand vinyl quinoline, vinyl pyrrolidone or vinyl v arylamines, such asparaaminostyrene, or polyamines prepared by reacting polymeric epoxycompounds with ammonia or primary or secondary amines, with polymerizable unsaturated alcohols, acids or esters, such as acrylates andmethacrylates of long chain fatty acids,- and the like. pounds are thosecontaining-tertiary amine groups and particularly those containingheterocyclic amino groups such as obtained by copolymerizing apolymerizable heterocyclic nitrogen base compound with a polymerizableunsaturated material free of heterocyclic nitrogen-containing radicalssuch as are described in British patent specification 760,554 and US.Patents 2,839,512 and 2,889,282. The copolymers include: (A) copolymerof stearyl methacrylate, and Z-methyl-S-vinyl pyridine; (B) copolymer ofstearyl methacrylate, lauryl methacrylate and 2-methyl-5-vinyl pyridine;and those which contain additional C alkyl methacrylates in the polymer,such as (C) copolymers of stearyl met-hacrylate, lauryl methacrylate,methyl methacrylate and Z-methyl-S-vinyl pyridine; and similarcopolymers in which the methyl methac- '1lhe preferred polymeric aminoor aimido com- W lauryl methacrylate and diethylaminoethylmethacry-late.

(note US. Patent 2,737,496).

Particularly preferred detergent polymers are Acryloid 917 and 966(copolymers of N-vinyl pyrrolidone and lauryl methacrylate in themolecular weight range of 4,000 to 1,000,000) or the copolymers of vinylpyridine and mixtures of dissimilar methacrylate esters, such ascopolymers (B) or (C) prepared by the methods described in US. patentsmentioned above and having molecular weight in the range of 450,000 and850,000 as determined by the light scattering method.

The oxygen-containing detergents include copolymers of C alkyl acrylatesand w-hydroxy alkyl methacrylates, e.g., (F) copolymer of stearylmethacrylate, lauryl methacrylate and Z-hyd-roxyethyl methacrylate.Other examples of suitable copolymers are those described in US. Patents2,800,453 and 3,033,828. These polymers are present in the oil inamounts ranging from about 1% to about 10%, preferably fromabout 1.5% toabout 5% by weight.

The mineral lubricating oil base may be derived from a variety ofpetroleum base stocks and are preferably paraflinic and/or naphthenic incharacter; they may also contain substantial proportions of hydrocarbonshaving aromatic character. The viscosity may vary within wide limits sothat the oils may belong, for example, to SAE classes 5W, W, 20W, 20,30, 40, 50, 60, or 70. Suitable oils may be derived from highlypa-rafiinic crudes in which case distillation and/ or dewaxing maybesuflicient to provide -a suitable base stock; chemical or selectivesolvent treatment may be used if desired, but is preferably kept to aminimum for economic reasons. Mixed-base crudes and even highly aromaticcrudes which contain paraflinic hydrocarbons also provide suitable oilbase stocks after refining by well-known techniques such as theseparation of distillate fractions of suitable boiling range followed bysolvent extraction with selective solvents, for example, furfural orphenol, to provide rafiinate fractions, dewaxing, and chemicaltreatment, for example, sulfuric acid treatment. 7 V

Illustrative compositions of the present invention are as follows:

Composition (a):

Mixture (Ia), percent mole 0.3 Copolymer (C) stearyl methacrylate/laurylmethacrylate/2 methyl 5-viny1 pyridine ,(MW=800,000), percent wt. 1.5Mineral lubricating oil Balance Composition (b):

Mixture (Ia), percent mole 0.3 Copolymer (D) lauryl methacrylate andN-vinyl pyrrolidone (MW==450,000), percent wt. 5 Mineral lubricating oilBalance Composition (c):

Mixture (Ha), percent mole 1.15 Copolymer (C), percent wt. 5 Minerallubricating oil Balance Composition (d):

Mixture (Illa), percent mole 0.6 Copolymer (C), percent wt. 1.5

Dicresyl phosphate, percent wt. 0.04 'I n'cresyl phosphate, percent wt.0.8 Mineral lubricating oil Balance Composition (e); w Mixture (Ia),percent mole 0.3 Copolymer (F), percent wt. 1.5 Mineral lubricating oilBalance In the LS-3 Cadillac Engine Test operated under the.

following conditions: 400 repeating cycles of 15 minutes each,comprising 1 minute at 90 F. jacket temperature, 10 minutes at 135. F.jacket temperature and 2500 r.p.m.- and 4 minutes at 190 F. jackettemperature at 3200 r.p.m., using high sulfur (1%) fuel, the resultswere as follows: Composition (a) ran for over 100 hours at which timethe engine was clean, free of sludge and corrosion and otherwise inexcellent condition. When Composition (a) was modified by removing thetritolyl phosphite and this modified phosphorus-free compositionidentified as Composition (X) was used in the LS-3 test and visiblesludge formation was noted at end of 40 hours and engine had to bestopped. Essentially the same results are obtainable using Compositions(b), (c), or (d) of the present invention as were obtained withComposition (a).

On the other hand when, in composition (X) the bis(3,5-

di-tertiary-butyl 4-hyd-roxyphenyl)methane was substituted with equalamount (0.3% mole) of tritolylphosphite to form Composition (Y) andengine tested (LS-3 condition), operation of the engine had to beterminated.

' at the end of 20 hours because of heavy sludge formation.

For purpose of clarity the formulation of Compositions (X) and (Y) areas follows:

Composition (X):

Bis(3,5-ditert.butyl 4-hydroxyphenyl)methane,

percent mole Copolymer (C) stearyl methacrylate/lauryl methacrylate/2methyl 5 vinyl pyridine Additive mixture of the present invention can bealso used to improve fuels, fuel oils, greases, asphaltsgoil.

emulsions and the like.

We claim as our invention:

1. A mineral lubricating oil composition comprising a major amountof'mineral lubricating oil and from about 1% to about 10% of a copolymerof Z-hydroxyethyl methacrylate and a mixture of lauryl and stearyl methacrylates and from about 0.01% to about 2% each'of- (A) an alkylatedbisphenol having the formula )n )n where Y is a radical selected fromthe group consisting of CH and -S, X is a halogen, R is a tertiaryalkyl' radical of 4 to 8 carbon atoms and m and n are integers such thatm is at least 1 and n can be zero and (B) an organic phosphite havingthe formula where Z is an element selected from the group consisting ofoxygen and sulfur, R is an aryl radical and x-I-y equal 3 and y is atleast 2. 2. The composition of claim 1 where Y is -CH ,n is zero, Z isoxygen, and y is zero and x is 3.

3. A mineral lubricating oil composition comprising a major amount ofmineral lubricating oil and from about 1% to about 10% of a copolymer of2-hydroxyethyl. methacrylate and a mixture of lauryl and stearylmethacrylates and from about 0.01% to about 2% eachof 5bis(3,5-di-tertiary-butyl-4 hydroxypheuyDmethane and tritolyl phosphite.

4. A mineral lubricating oil composition comprising a major amount ofmineral lubricating oil and from about 1% to about 10% of a copolymer ofZ-hydroxyethyl methacrylate and a mixture of lauryl and stearylmethacrylates and from about 0.01% to about 2% each ofbis(3,5-di-tertiarybutyl 4-hydroxyphenyl)methane and ditolyl phosphite.

References Cited by the Examiner UNITED STATES PATENTS 2,188,943 2/1940Evers 252-46.6

6 2,758,091 8/1956 Webber 25249.9 3,100,749 8/1963 Wittner et a1.252--49.9 3,115,465 12/1963 Orloif et a1 252-499 3,215,631 11/1965Henderson et a1. 252-499 5 OTHER REFERENCES 845,255 8/ 1960 GreatBritain. 1,299,534 6/ 1962 France.

10 DANIEL E. WYMAN, Primary Examiner.

W. H. CANNON, Assistant Examiner.

1. A MINERAL LUBRICATING OIL COMPOSITION COMPRISING A MAJOR AMOUNT OFMINERAL LUBRICATING OIL AND FROM ABOUT 1% TO ABOUT 10% OF A COPOLYMER OF2-HYDROXYETHYL METHACRYLATE AND A MIXTURE OF LAURYL AND STEARYLMETHACRYLATES AND FROM ABOUT 0.01% TO ABOUT 2% EACH OF (A) AN ALKYLATEDBISPHENOL HAVING THE FORMULA